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kobo-book-downloader
A tool to download and remove DRM from your purchased Kobo.com ebooks and audiobooks.
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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
I maintain a tool for removing DRM from kobo books, which does preserve the metadata on the epub. https://github.com/subdavis/kobo-book-downloader
Apprentice Alf's De-DRM (https://github.com/apprenticeharper/DeDRM_tool) removes DRM from new Amazon and Amazon Rental books (with modification). Don't know about Google.
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